Non-catalytic pyrolysis of residues from aromatic carboxylic acid manufacture

Commercially attractive amounts of benzene and toluene can be obtained from a solid mixture of aldehydo-, carboxy-, keto- and carboxy-, carboxy- and aldehydo-substituted benzene and toluene including such mixtures also containing cobalt and manganese salts of organic acids and inorganic and organic bromides obtained from the manufacture of benzene di- and tricarboxylic acids by non-catalytic pyrolysis of such mixture or gases and vapors therefrom at a temperature of at least 700 DEG C. Such non-catalytic pyrolysis is more technically attractive than catalytic pyrolysis conducted at a temperature of from 300 DEG C. to 500 DEG C. which has a short activity life.